Second Five-Year Review Completed, Ralston Superfund Site, Cedar Rapids, Linn County, Iowa
The U.S. Environmental Protection Agency (EPA) conducts regular five-year reviews on Superfund sites where cleanups have been conducted. These reviews are required by the Superfund law [42 U.S.C. Section 9621(c)]. EPA Region 7 has completed the second five-year review of the Ralston site in Cedar Rapids, Linn County, Iowa.
The Ralston site is located north of 228 Blairs Ferry Road in northern Cedar Rapids, Iowa. The site is currently owned by Rockwell Collins Inc. (Rockwell) and is fenced. In 1981 Rockwell notified the EPA of the wastes disposed at the site. From about 1956 to 1958, the site was used by Rockwell as a disposal area for wastes generated from a pilot gold plating operation as well as other industrial wastes. The amount of liquid wastes disposed at the site is not known but was estimated to have been as much as 60,000 gallons. The wastes were typically burned and spread in layers. The types of wastes disposed at the site by Rockwell included solvents, paint sludge, and general industrial refuse such as scrap metal, office furniture, and construction and demolition debris. Cyanide wastes, encapsulated in concrete, were alsodisposed at the site. The Ralston site was not restricted solely for the use of Rockwell so other local businesses likely disposed of solid wastes there as well.
In 1985 an EPA contractor conducted a preliminary assessment of the site and determined ground water and surface water may have been impacted. In 1990 Rockwell began investigations at the site under the oversight of the EPA. The primary contaminants found at the site are chlorinated volatile organic compounds (VOCs). They include trichloroethene, cis-1,2-dichloroethene, and vinyl chloride. The last two compounds listed occur when trichloroethene breaks down in the environment.
In order to accelerate the cleanup of the disposal area and shallow ground water, Rockwell agreed to conduct a removal action. This work began in 1993 and included:
- capping the former disposal area;
- stabilizing the Dry Run Creek bank;
- installation and operation of a dual vapor extraction and treatment system; and
- extraction and treatment of shallow ground water north of Dry Run Creek.
Rockwell also removed and disposed of two drums of concrete-encapsulated cyanide and connected two residences to a public water supply when it was found their wells were contaminated. In 1999 following the completion of these removal actions, a remedial investigation and feasibility study, and an opportunity for public comment on the proposed remedy for the site, EPA presented the selected remedy in a Record of Decision (ROD). The selected remedy included the following actions:
- monitored natural attenuation of the ground water;
- maintain institutional controls at the site; and
- maintenance of the disposal area cap and Dry Run Creek bank stabilization.
The institutional controls include listing on the Iowa Registry of Hazardous Waste Disposal Sites, designation of a protected ground water source area surrounding the site, and continued ownership of the fenced disposal area by Rockwell.
In 2000 the Iowa Department of Natural Resources (IDNR) took over the enforcement lead for this site from the EPA and has overseen the implementation of the remedial actions at the site. Since that time, Rockwell has been conducting the remedial actions pursuant to a Consent Order with the IDNR.
THE FIVE-YEAR REVIEW
The first five-year review in 2006 concluded that the remedy was protective of human health and the environment. During this five-year review, EPA will inspect the site and study site information to determine whether the remedy continues to be protective. We encourage the community to tell us about site conditions or any concerns.
At the end of the review, a final report will be prepared and will be available in the site information repositories and on EPA's website.
Detailed site information can be found in the Ralston Administrative Record, at the following locations during regular business hours:
Cedar Rapids Public Library
500 1st Street SE
Cedar Rapids, Iowa
EPA Records Center
901 N. Fifth Street
Kansas City, Kansas
Questions or requests for information can be addressed to:
Community Involvement Coordinator
U.S. EPA Region 7
901 North Fifth St.
Kansas City, KS 66101
Toll-free: (800) 223-0425